Compositions for eliminating human and animal excrement smells

ABSTRACT

The present invention relates to compositions (deodorizing or not) for human and animal excrement, especially pest and livestock, comprised of acidic agents and water soluble polymers, wherein the acidic agents are base neutralizers for the ammonia and indolic amines in the excrement and the water soluble polymers are barrier forming agents for the vapor of the offensive odor producing compounds in the excrement and for slowing down the air oxidative and enzymatic nitrification of the excrement ammonia and organic nitrogen thus dispersing and attenuating nitrate concentrations in the environment. The present invention further relates to a method of applying said compositions to excrement. Said compositions may be applied to excrement in liquid form by mixing the liquid composition together with the excrement, or in form of a spray, by spraying the composition directly on to the excrement.

This application is a 371 of PCT/IL98/00016 filed Jan. 14, 1998.

FIELD OF THE INVENTION

The present invention relates generally to deodorant compositions forhuman and animal excrement and to a method for their use. The term“animal” as used in this specification refers especially to pets andlivestock. More specifically the present invention relates to novelcompositions, preferably aqueous compositions, comprises of acidicagents and water soluble polymers for applying on excrement, that areuseful as deodorant compositions and for attenuating and dispersingnitrate concentrations in the environment and in the water reservoir,wherein the deodorizing of the excrement is based on acidification byorganic acids and excrement coating by water soluble polymers which actas barriers for the offensive odor producing compounds of the excrementand form, upon drying, a film, turning the excrement into solid cakeseasy to handle and with no perceptible odor.

BACKGROUND OF THE INVENTION

Owners of animals such as pets and livestock alike face problems causedby animal excrement; its foul odor and the need to eliminate it. Humanexcrement, such as in out houses in camp sites and army camps, pose thesame problems. National and international regulations require thatmaterials used for treating excrement, be non toxic and friendly to theenvironment, in particular that they do not contribute to addingnitrates or phosphates to the water reservoir. Additional requirementsof commercial deodorizing compositions are low cost, simplicity of usein and outdoors and efficient deodorizing of excrement in liquid andsolid forms. The principle targets of most existing treatment methodsfor preventing offensive odors of animal excrement, are ammonia andindolic amines. The common method to prevent offensive odors and retardbacterial and enzymatic decomposition is converting these compounds totheir much less volatile ammonium salts by various organic and inorganicacids or their salts, as described in numerous publications.

Although acidification prevents offensive odors originating from basicammonia and amines, it intensifies the offensive odors due to theexcrement's volatile ammonium salts by various organic and inorganicacids or their salts, as described in numerous publications.

Although acidification prevents offensive odors originating from basicammonia and amines, it intensifies the offensive odors due to theexcrement's volatile organic acids such as acetic, propionic and butyricacids, due to the stabilization of their non ionized form. Furthermore,feces of low mobility do not come into full contact with the deodorizingagents which are usually absorbed or sprayed on pet's litter and henceare only partially deodorized. Therefore, these is a need for aninexpensive, effective and environment friendly composition which willinclude an impermeable barrier to excrement offensive odors in additionto safe deodorizing treatment of ammonia and idolic amines. Thisimpermeable barrier has an additional advantage of slowing down the airoxidative and enzymatic nitrification of the excrement ammonia andorganic nitrogen leading to dispersion and attenuation of nitrateconcentrations in the environment. Of the known deodorizing formulationsfor pet and livestock few, if any, are of practical use. Use is made ofcross-lined polymer gels, as water absorbing materials, in compositionsfor treatment of pet excrement, in several patents. Japanese patents5,269,164, 3,290,126 and 2,238,834 disclose polymer gels with high waterabsorbing capacity for absorbing animal excretions. These gels maypreviously be blended with deodorant agents. Japanese patent 63185323discloses absorbents for deodorizing pet excrement's. Polyvinyl alcoholis used as a binder in the production of pellets comprises of waterabsorbing inorganic polymers, like zeolites, and water soluble inorganicsalts. U.S. Pat. No. 5,039,481 describes NH₃ scavenging deodorant madeof aliphatic polycarboxylic acids for treatment of livestock excrement.Japanese patents 61119127 and 62153348 describe compositions fortreating pet feces with a water insoluble coating to reduce odors and toenable feces to be removed by hand. These compositions, however,comprise toxic and ecologically unsafe volatile organic solvents such asacetone, methylene chloride, benzene, CFCl₃ and the expensive and toxiccyanoacrylic acid monomer.

The present invention describes novel deodorizing compositionscomprising organic acids and water soluble polymers for excrementcoating, which meet the above mentioned requirements. Furthermore, thepresent invention overcomes the two above mentioned major limitations ofoffensive odor due to stabilizing the non ionized form of excrement'svolatile organic acids and low mobility feces not coming in full contactwith the deodorizing composition, by incorporating water soluble barrierforming agents in the deodorant composition.

SUMMARY OF THE INVENTION

The present invention relates to deodorizing compositions for human andanimal excrement, especially pets and livestock, comprised of acidicagents and water soluble polymers, wherein the acidic agents are baseneutralizers for the ammonia and indolic amines in the excrement and thewater soluble polymers are film forming polymers, of molecular weighthigher then 15,000, forming a barrier [forming agents] for the vapor ofthe offensive odor producing compounds in the excrement. The presentinvention also relates to compositions (not necessarily deodorantcompositions) comprised of acidic agents and water soluble polymerswherein the water soluble polymers are barrier forming agents useful forslowing down the air oxidative and enzymatic nitrification of theexcrement ammonia and organic nitrogen thus dispersing and attenuatingnitrate concentrations in the environment and in the water reservoir.These composition are preferably an aqueous solution. The presentinvention further relates to a method of applying said compositions toexcrement. Said compositions may be applied to excrement in liquid formby mixing the liquid composition together with the excrement. Thismethod is especially useful in treating livestock excrement. Saidcompositions may also be applied in form of a spray, by spraying thecomposition directly on to the excrement whereas, upon drying, thesprayed compositions form a thin film turning the excrement into solidcakes, easy to handle with no perceptible smell.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to novel deodorizing compositions,preferably aqueous compositions, for human and animal excrementcomprised of acidic agents and water soluble polymers, wherein theacidic agents are base neutralizers for the ammonia and indolic aminesin the excrement and the water soluble polymers are barrier formingagents for the vapor of the offensive odor producing compounds in theexcrement. When applied on excrement these compositions form, upondrying, thin film barriers which greatly reduce the vapor pressure ofthe offensive odor producing compounds and the intensified offensiveodors due to the acidification which stabilizes the non ionized form ofthe excrement's volatile organic acids such as acetic, propionic andbutyric acids. In the case of solid feces this film also traps theammonia and indolic amines that may escape contact with the deodorizingagent. These compositions form, upon drying, a thin film turning theexcrement into solid cakes, easy to handle with no perceptible smell.The acidic agents are preferably biodegradable organic acids or theirsoluble salts such as citric acid, glycolic acid, oxalic acid,polyacrylic acids, preferably in a concentration range of 1%-10%. Thewater soluble polymers are preferably hyroxyethyl cellulose,polyethylene oxide, polyvinyl pyrrolidone, polyhydroxyethyl(meth)acrylate, polyvinyl alcohol, polyhydroxypropyl (meth)acrylate,poly(meth)acrylamide, which are biologically degradable, non toxic andecologically safe, preferably in a concentration range of 0.1%-10%. Afragrance, such as limonene, may be added to the compositions as naturalfragrance. The water soluble coating polymers (WSCP) used in thisinvention are biodegradable, non toxic and friendly to the environmentand can be included in various deodorizing compositions. The saidinvention will be further illustrated in detail by the followingexamples. These examples do not intend to limit the scope of theinvention but to demonstrate and clarify it only. In the followingexamples WSCP were added to compositions based on aqueous solutions ofcarboxylic acids or combinations of carboxylic acids or their solublesalts. These compositions were applied to different animal excrements.

EXAMPLE 1

solution 1:5% (w/v) of polyvinyl alcohol (PVA) was obtained bydissolving 10 g of PVA (98% hydrolyzed, avg. M.W.=16,000) in 200 ml tapwater (800 mho conductivity at 70° C. Composition 1.1 (2.5% PVA), acomposition suitable for pets excrement was prepared from the following:

solution 1 125 ml water 125 ml citric acid 12.5 g monopotassiumphosphate (MKP) 12.5 g limonene 10 μl

Composition 1.2 (1.5% PVA), a composition suitable for pets excrementand transported organic fertilizer, was prepared from the following:

1.5% PVA 1000 ml citric acid 100 g limonene 20 μl

Composition 1.1 was tested on cat litter in a family's home. 100 ml ofcomposition 1.1 were sprayed on 2 kg of smelly cat litter, whileslightly mixing the litter. Uncovered feces were occasionally sprayedlightly and brushed aside. A spraying bottle of 250 ml was used for twolitter replacements in a three week period. During this time theexcrement offensive smell was reduced significantly and replacement ofthe litter was needed only every 10 days as opposed to every 4 days,without treatment. On completion of the experiment with composition 1.1,composition 1.2 was tested on the same cat litter with similardeodorizing efficiency results.

EXAMPLE 2

This example shows a composition suitable both for pet excrement and forspraying on transported organic fertilizer.

Composition 2

1.5% polyvinyl alcohol aqueous solution 100 ml Citric acid 5 g

The citric acid was dissolved in 7 ml water and the solution was slowlyadded to the polyvinyl alcohol solution while stirring. 40 ml of thissolution were mixed with 200 ml of pig excrement collected from acesspit adjacent to the sty. The pH of the excrement was reduced from 7to 6. 200 ml of a control (excrement with no addition) were placed in anopen beaker about 10 m apart from the excrement treated with composition2 in the open air.

After one hour in the sun a barrier film formed on the surface of thetreated solution, preventing smell and protecting the underlyingexcrement from flies. The polyvinyl alcohol—citric acid solution wastested on cat litter as described in example 1. Similar results wereobtained and the replacement of the litter was not required for 10 daysafter the initial spray.

EXAMPLE 3

This example shows the effect of acidification in an aqueous media, suchas oxidation ponds and livestock excrement pools. Three samples of 20liters of pig excrement, collected from a cesspit adjacent to the sty,were added to three 30 liter plastic tanks with a continuous air supplyfrom air pumps. The three samples were treated with the following:

Composition 3.1

450 ml glycolic acid (70%) 107 ml ethylene glycol 300 g ferrous sulfateheptahydrate

Composition 3.2

450 ml glycolic acid (70%) 300 g ferrous sulfate heptahydrate

Control (no addition)

The initial pH of the excrement was 7.1 (measured using a glasselectrode). Addition of compositions 3.1 and 3.2 brought the pH to 4.5and 4.6 respectively. The tanks were allowed to stand outdoors for sixmonths. The water lost due to evaporation was periodically replaced tomaintain a constant volume.

After six months the following observations were made:

composition 3.1 composition 3.2 control pH 5.92 6.12 6.77 color brownbrown black smell moderate moderate foul fly maggots none none several

EXAMPLE 4

This example demonstrates the effect of the polymers as barrier formingagents. The water was decanted from the three tanks from example 2(after 6 months) and the following solutions were added to about 5liters of the residual sludge:

to 3.1450 ml of a 10% polyvinyl pyrrolidone solution.

to 3.2260 mo of an 8% polyethylene oxide solution. the tanks were leftin the sun for a week and the sludge dried out. Sample 3.2 dried into asolid cake which could easily be handled and had no perceptible smell.Sample 3.1 dried into a less strong cake and had a slight residualsmell. The control sample was dispersed and had a residual smell, butless than when it was mixed with water.

EXAMPLE 5

This example shows the effect of polyvinyl pyrrolidone as a barrierforming agent in cat litter. A solution of 15 g of citric acid in 200 mlof water was added to 200 ml of a 2% solution of polyvinyl pyrrolidonewith stirring. The pH of the solution formed by mixing was about 1.5.This mixture solution was sprayed on cat litter as described in example1.

The excrement offensive smell was significantly reduced and replacementof the litter was needed only every 10 days as opposed to every 4 days,without treatment.

What is claimed is:
 1. A method of deodorizing human and animalexcrement, comprising the steps of: spraying an aqueous deodorizingcomposition on said excrement, said aqueous deodorizing compositionconsisting essentially of one or more carboxylic acids in an amountsufficient to neutralize nitrogenous odor-generating components in saidexcrement, and water soluble film forming polymers in quantitiessufficient to form a solid film over the bulk of said excrement; andallowing the aqueous deodorizing composition to dry until the watersoluble film forming polymers form the solid film over the bulk of saidexcrement, thereby greatly reducing a vapor pressure of offensive odorproducing compounds and facilitating easy handling of said deodorizedexcrement.
 2. A method of deodorizing excrement of at least one oflivestock, animal and human, comprising the steps of: mixing an aqueousdeodorizing composition with said excrement, said aqueous deodorizingcomposition consisting essentially of one or more carboxylic acids in anamount sufficient to neutralize nitrogenous odor-generating componentsin said excrement, and water soluble film forming polymers in quantitiessufficient to form a solid film over the bulk of said excrement; andallowing the aqueous deodorizing composition to dry until the watersoluble film forming polymers form the solid film over the bulk of saidexcrement, thereby blocking volatile odor-generating components andfacilitating easy handling of said deodorized excrement.